FIG. 26 shows a conventional example of an optical connector which is to be connected to a coated optical fiber.
The optical connector 201 shown in the figure is disclosed in Patent Reference 1 below, and includes: a ferrule 203 which incorporates a short first incorporated optical fiber (bare optical fiber) 202; and a splice member 204 which holds the ferrule 203 and the incorporated optical fiber 202 that is projected from the rear end face of the ferrule 203. The optical connector 201 has a configuration where a coated optical fiber 219 is introduced from the rear side into the splice member 204, the incorporated optical fiber 202 is butted against a bare optical fiber 220 which is exposed from the tip end of the coated optical fiber 219, and the splice member 204 is clamped to be fixed to the coated optical fiber 219.
In order to prevent the transmission characteristics of the connecting portion of the bare optical fibers from being lowered, a first refractive index matching material 221 is injected into a region where the rear end face of the incorporated optical fiber 202 and the front end face of the bare optical fiber 220 are butted against each other, and a second refractive index matching material 222 is injected into a bare-optical fiber introducing portion 210 disposed in the splice member 204.
Patent Reference 1: JP-A-11-160563